What is a soundpost? What does it do? Luthier Cecilia González from the Women in Lutherie community illustrates the enormous role of the little cylindrical piece of wood in an aim to demystify the subject for players

A soundpost is a cylindrical piece of spruce wood that is wedged between the front and back plates inside a violin family instrument (violin, viola, cello, double bass). It is introduced through the treble f-hole and positioned under the treble foot of the bridge. It is fitted with tension, so that it can stand on its own without any glue. The soundpost has a major acoustical and structural effect on an instrument, and its main function is to transmit the vibrations of the string from the top plate to the back plate, while it supports the front and counteracts the stresses of string tension.

The traditional soundpost position on a violin is: the thickness of the bridge foot, divided by two. Take that measurement, from the back of the treble foot of your instrument down, and that should be where the top of the soundpost fits. For example: the foot of your bridge is 5mm, so the soundpost should sit 2.5mm down.

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